Which is the best description of the traditional form of a tanka?

 Tanka typically consist of a pattern of 5-7-5-7-7

It developed as a reaction to the impact of european colonialism in africa on peoples of african descent. in the  mid-20th century, activists in africa adopted pan-africanism as a rallying cry for independence from colonial rule. some african pan-africanists sought to unite the continent as one independenthope it was useful